Dynamic Hyperinflation and Mechanical Ventilation

Treating reversible factors like bronchospasm and secretions improves airflow, reduces work of breathing, and enhances oxygenation.

Increasing expiratory time by decreasing the I:E ratio allows more time for exhalation, reducing air trapping and improving respiratory mechanics.

Measuring PEEPi helps assess the degree of dynamic hyperinflation and informs management strategies to optimize ventilation.

<p>Setting exogenous PEEP to about 2/3 of PEEPi improves gas distribution and reduces the work required for inspiratory triggering.</p> Signup and view all the answers

<p>Disconnecting allows spontaneous exhalation, relieving pressure and facilitating breathing before reconnecting to the ventilator.</p> Signup and view all the answers

<p>Bronchospasm increases expiratory resistance, leading to higher PEEP levels.</p> Signup and view all the answers

<p>Impaired elastic recoil, particularly in emphysema, reduces the lungs' ability to expel air, necessitating higher PEEP to maintain adequate ventilation.</p> Signup and view all the answers

<p>Narrowed or kinked endotracheal tubes and inspissated secretions increase expiratory resistance, leading to higher PEEP.</p> Signup and view all the answers

<p>Inadequate expiratory time causes incomplete lung emptying, which increases minute ventilation and therefore requires higher PEEP to optimize inhalation.</p> Signup and view all the answers

<p>An HME filter can increase expiratory resistance due to moisture or bacterial buildup, leading to an elevation in PEEP.</p> Signup and view all the answers

<p>Dynamic hyperinflation occurs when air is trapped in the lungs during expiration, leading to an increase in intrathoracic volume associated with high PEEP levels.</p> Signup and view all the answers

<p>Increased intrathoracic volume raises airway pressures required for a given tidal volume, leading to a higher risk of barotrauma.</p> Signup and view all the answers

<p>Increased intrathoracic pressure decreases venous return and preload, which can result in reduced cardiac output.</p> Signup and view all the answers

<p>High PEEP increases the inspiratory work needed to trigger the ventilator due to heightened intrathoracic pressure.</p> Signup and view all the answers

<p>The risks include lung injury, pneumothorax, and potentially fatal respiratory complications.</p> Signup and view all the answers

<p>Hypotension can occur due to decreased cardiac output from reduced venous return caused by increased intrathoracic pressure.</p> Signup and view all the answers

<p>'Breath stacking' refers to the accumulation of air in the lungs due to inadequate expiration, exacerbated by high PEEP settings.</p> Signup and view all the answers

<p>The expiratory hold maneuver is performed to allow alveolar pressure to equilibrate with airway pressure, providing an accurate measurement of PEEP.</p> Signup and view all the answers

<p>The optimal duration for expiratory circuit occlusion is 3-5 seconds.</p> Signup and view all the answers

<p>During an expiratory hold maneuver, alveolar pressure equilibrates with airway pressure, indicating the level of intrinsic PEEP.</p> Signup and view all the answers

<p>The graph displays pressure, flow, and volume curves; these illustrate the physiological changes during the expiratory breath hold, significant for understanding ventilation mechanics.</p> Signup and view all the answers

<p>Intrinsic PEEP refers to the unintentional positive end-expiratory pressure that remains in the lungs due to incomplete expiration.</p> Signup and view all the answers

<p>The expiratory flow curve does not reach baseline.</p> Signup and view all the answers

<p>There is a drop in blood pressure (hypotension).</p> Signup and view all the answers

<p>They suggest the presence of dynamic hyperinflation.</p> Signup and view all the answers

<p>It indicates possible airway obstruction or bronchospasm.</p> Signup and view all the answers

<p>It shows trapped volume during expiration that was not fully exhaled.</p> Signup and view all the answers

<p>It reflects the presence of air trapping in the lungs.</p> Signup and view all the answers

<p>It allows for observation of prolonged exhalation and change in pressures.</p> Signup and view all the answers

<p>It illustrates the pressure changes over time during breathing.</p> Signup and view all the answers

<p>It indicates an increased risk of respiratory failure due to air trapping.</p> Signup and view all the answers

<p>They can reveal the severity of airway obstruction and effectiveness of ventilation.</p> Signup and view all the answers

<p>Intrinsic PEEP is the positive pressure that remains in the lungs at the end of expiration due to factors hindering expiratory flow; it is significant as it can affect gas exchange and lead to respiratory complications.</p> Signup and view all the answers

<p>Bronchospasm and airway secretions are two causes of intrinsic PEEP, which can impede expiratory flow and increase work of breathing.</p> Signup and view all the answers

<p>Intrinsic PEEP can lead to dynamic hyperinflation, decreased tidal volumes, and increased airway resistance, complicating ventilation efforts.</p> Signup and view all the answers

<p>Management strategies include adjusting ventilator settings, using bronchodilators, suctioning secretions, and addressing underlying conditions.</p> Signup and view all the answers

<p>Intrinsic PEEP arises from dysfunctional expiratory flow within the patient's lungs, while extrinsic PEEP is a controlled pressure applied externally by the ventilator.</p> Signup and view all the answers

<p>Intrinsic PEEP is generated within the respiratory system due to expiratory flow impediments, while extrinsic PEEP is actively applied by the ventilator.</p> Signup and view all the answers

<p>Bronchospasm and mucus plugging are two causes of intrinsic PEEP due to airway obstruction.</p> Signup and view all the answers

<p>Intrinsic PEEP impedes complete expiration, leading to reduced tidal volume during inspiration.</p> Signup and view all the answers

<p>Identifying and addressing the underlying cause of intrinsic PEEP is crucial for effective management.</p> Signup and view all the answers

<p>High intrinsic PEEP can lead to reduced lung compliance, making the lungs stiffer.</p> Signup and view all the answers

<p>Proper management of intrinsic PEEP is essential to prevent lung injuries like barotrauma and volutrauma.</p> Signup and view all the answers

<p>High inspiratory pressures can exacerbate air trapping, leading to increased intrinsic PEEP.</p> Signup and view all the answers

<p>Increased intrinsic PEEP can decrease venous return and cardiac output due to elevated intrathoracic pressure.</p> Signup and view all the answers

<p>Adjusting the inspiratory flow rate, inspiratory time, or tidal volume can help.</p> Signup and view all the answers

<p>Head-of-bed elevation and maneuvers to improve lung recruitment can significantly help.</p> Signup and view all the answers

<p>Neuromuscular blockade may be necessary to reduce the work of breathing in severe cases.</p> Signup and view all the answers

<p>Careful titration is necessary to avoid over-sedation, which can worsen respiratory drive.</p> Signup and view all the answers

<p>NIV provides respiratory support without intubation, potentially reducing elevated intrinsic PEEP.</p> Signup and view all the answers

<p>Higher flow rates can reduce intrinsic PEEP by minimizing the time spent at high lung volumes, while lower flow rates might exacerbate it by prolonging the inspiratory phase.</p> Signup and view all the answers

<p>Shortening inspiratory time can reduce intrinsic PEEP by decreasing the duration of high lung volumes.</p> Signup and view all the answers

<p>Elevating tidal volume can help diminish intrinsic PEEP by ensuring more effective lung emptying and preventing trapped air.</p> Signup and view all the answers

<p>Intrinsic PEEP is a non-dependent pressure within the lungs due to delayed exhalation, and it increases the work of breathing for the patient.</p> Signup and view all the answers

<p>Factors like airway resistance, lung compliance, and respiratory rate greatly affect the levels of intrinsic PEEP generated.</p> Signup and view all the answers

Airflow resistance during exhalation is increased, making it harder to breathe out.

Constriction of the airways, making it difficult to exhale.

A narrowed or bent breathing tube makes it difficult to exhale.

Thick mucus buildup in the airways obstructs airflow during exhalation.

The lung's ability to spring back after inspiration is reduced, causing air to be trapped in the lungs.

A situation where the lungs become overly inflated due to the inability to fully exhale, caused by high PEEP levels.

The pressure applied to the airways at the end of expiration to keep them open.

The increased volume of air inside the chest cavity due to excessive inflation.

The increased pressure inside the chest cavity due to increased intrathoracic volume.

Injury to the lungs caused by excessive pressure.

Reduced blood flow back to the heart, leading to decreased blood volume.

Difficulty breathing due to increased intrathoracic pressure, making it harder to take a breath.

Treating reversible factors such as bronchospasm, secretions, and expiratory devices can improve lung function and ventilator management.

Prolonging expiratory time, achieved by decreasing the inspiratory-to-expiratory (I:E) ratio, respiratory rate (RR), or increasing inspiratory flow, helps prevent air trapping and improve gas exchange.

Decreasing tidal volume reduces lung stress and improves ventilation-perfusion matching, especially in patients with lung injury.

PEEPi (expiratory hold) measures the pressure required to prevent alveolar collapse at the end of exhalation.

Setting exogenous PEEP to approximately two-thirds of PEEPi can improve gas distribution and reduce inspiratory effort, but ZEEP (zero PEEP) may also be considered.

A method used to measure the pressure remaining in the lungs at the end of a breath, even after the patient has exhaled.

The pressure measured during the expiratory hold maneuver, representing the pressure remaining inside the lungs after exhalation.

During the maneuver, the patient's airway is temporarily blocked (occluded) for a short time (3-5 seconds) to stop airflow. This allows the pressure inside the lungs to reach the same pressure as the pressure in the airways.

The pressure in the lungs is allowed to equalize with the pressure in the airways.

The expiratory hold maneuver is performed at the end of a normal exhalation, allowing the pressure in the lungs to stabilize before measurement.

The pressure in the lungs at the end of a normal exhale.

The pressure in the lungs when the lungs are full.

The amount of air a person breathes in and out.

The rate at which air moves in and out of the lungs.

A way to measure airflow during breathing, showing how air flow changes over time.

Shows the pressure changes in the lungs over time.

A visual representation of how breathing volume changes over time.

A method to assess dynamic hyperinflation by observing the expiratory flow curve and seeing if it reaches baseline.

A method to assess dynamic hyperinflation by disconnecting the breathing tube and observing the patient's exhalation.

Intrinsic PEEP is the pressure remaining in the lungs at the end of exhalation, regardless of external ventilator settings. It occurs due to internal obstructions like airway narrowing or thick secretions slowing airflow out of the lungs.

The presence of iPEEP can be a sign of airway obstruction or decreased lung elasticity, and requires adjustment of ventilator settings to prevent complications like air trapping or lung injury.

Extrinsic PEEP is the pressure applied by the ventilator at the end of exhalation to keep the airways open. It's controlled by the machine.

iPEEP results from factors within the patient's respiratory system that hinder airflow out of the lungs, while Extrinsic PEEP is a controlled pressure applied by the ventilator.

Understanding both iPEEP and Extrinsic PEEP is crucial for effective ventilator management. Clinicians need to differentiate these pressures and adjust ventilator settings appropriately.

Intrinsic PEEP (iPEEP) is a positive end-expiratory pressure (PEEP) generated within the respiratory system. It occurs passively during mechanical ventilation as a result of factors impeding expiratory flow.

iPEEP can be caused by various factors like airway obstruction (bronchospasm, secretions), air trapping (high respiratory rate, delayed exhalation), high inspiratory pressures, decreased lung compliance (pulmonary edema), and secretions.

iPEEP increases the work of breathing because it requires more pressure to overcome during inspiration. It also reduces tidal volume as complete expiration is impeded, potentially reducing the volume of air inhaled.

High iPEEP can also lead to reduced lung compliance (stiffness), increased risk of barotrauma (lung injury from pressure), impaired gas exchange and oxygenation, negative cardiovascular effects (decreased venous return and cardiac output), and lung injury.

Addressing the underlying cause is key to managing iPEEP. This may involve treating bronchospasm, clearing secretions, reducing inspiratory pressures, and addressing lung compliance issues.

Prolonging expiratory time can improve exhale and reduce air trapping. This can be achieved by decreasing the inspiratory-to-expiratory (I:E) ratio, respiratory rate (RR), or increasing inspiratory flow.

Decreasing tidal volume reduces lung stress and improves ventilation-perfusion matching, especially in patients with lung injury.

PEEPi (expiratory hold) is a measurement of the pressure needed to prevent alveolar collapse at the end of exhalation. This helps determine if any iPEEP is present and guides PEEP setting.

iPEEP is important to address because it can be a sign of airway obstruction or decreased lung elasticity, and it can lead to complications like air trapping or lung injury. Knowing iPEEP can help clinicians adjust ventilator settings to improve lung function.

Adjusting ventilator settings like inspiratory flow rate, inspiratory time, or tidal volume can help to reduce iPEEP. Proper patient positioning, reducing sedation, and considering non-invasive ventilation can also be effective.

Prolonging expiratory time can help to improve exhale and reduce air trapping. This can be achieved by decreasing the inspiratory-to-expiratory (I:E) ratio, respiratory rate (RR), or increasing inspiratory flow.

iPEEP can make it much harder for patients to breathe because they have to push harder to get air in. It can also lead to air trapping, making the lungs stiff and more prone to injury.

The best way to deal with iPEEP is to find the reason it's happening. Are the airways narrowed? Are there thick secretions? Once the cause is known, we can treat it and make it easier for the patient to breathe.

Changing the settings on a ventilator can help reduce iPEEP. We can increase the flow rate to speed up inhalation, or extend the exhale time by decreasing the breathing rate. This gives the lungs more time to let air out properly.

Intrinsic PEEP is different from extrinsic PEEP, which is set by the ventilator. Extrinsic PEEP is a pressure applied at the end of exhalation to keep the airways open. But intrinsic PEEP is caused by factors within the patient themselves.